JP2005318193A - Ic tag, pallet and ic tag position calculator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To realize an IC tag which copes with both the immediate response at inquiry and reduction of the power consumption at normal times. <P>SOLUTION: An IC chip 20 in the IC tag 10 has a regular output unit 36 for periodically outputting output signals and a detector 32 for detecting a normally inputted signal, based on radio waves from the outside. When the detector 32 detects the input signal, a response unit 34 immediately processes it to send corresponding output signal to a transceiver circuit 40. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a technique related to a radio wave transmission / reception aspect of an IC tag or a peripheral technique related to this transmission / reception aspect.

  An IC tag (RFID) equipped with an IC (integrated circuit) chip and an antenna is becoming widespread. For example, the IC tag is incorporated in a pallet on which an article is loaded and transported, and is used for distribution and inventory management of the article.

  Patent Document 1 below discloses a technique for receiving a response wave corresponding to an interrogation wave emitted from an IC tag using a plurality of fixed antennas set at different positions and obtaining the position. ing.

JP 2001-116583 A

  When an article to which an IC tag is attached is passed through a lead / writer gate at the time of transportation or the like, the communicable time is limited. For this reason, the IC tag is desired to have a function capable of quickly responding to an inquiry from a read / writer gate. On the other hand, when stored in a warehouse or a container, it is not necessary to communicate frequently, and the communicable time can be relatively long. Therefore, the IC tag is required to periodically transmit a radio wave for informing its existence, and to operate with reduced power consumption. In addition, it may be preferable that the presence position of the IC tag can be detected.

  An object of the present invention is to realize an IC tag that achieves both quick response at the time of inquiry and reduction of power consumption during normal times.

  Still another object of the present invention is to develop a technology that makes it easy to grasp each IC tag in a situation where a plurality of IC tags are used.

  An IC tag according to the present invention includes an antenna that acquires an input signal by receiving radio waves and transmits a radio wave based on an output signal, a process that is connected to the antenna, and that is based on the input of the input signal and a process that outputs the output signal In the IC tag including the integrated circuit to perform, the integrated circuit includes intermittent output means for intermittently outputting the output signal at a set timing, detection means for constantly detecting the input signal, and the detection means Responding means for performing an immediately corresponding process and outputting an output signal for response when an input signal is detected.

  An IC tag integrated circuit is typically configured as an IC chip, and includes a transmission circuit, a reception circuit, a memory, a control unit, and the like. The antenna transmits radio waves based on the output signal processed by the transmission circuit, and processes the received radio waves by the reception circuit to obtain an input signal. The antenna may be physically common or different for reception and transmission.

  The intermittent output means transmits the output signal intermittently, that is, repeatedly at regular or irregular intervals. The optimum time interval varies depending on the use situation, but it is particularly desirable to be about 5 seconds to 20 seconds, for example. When there is a time allowance and there is a strong demand for suppressing power consumption, the length can be appropriately increased to about 1 minute, or about several minutes or several tens of minutes. The content of the output signal is not particularly limited, and for example, specific information for specifying the IC tag can be incorporated. The detection means always detects whether an input signal has been input. When there is an input, the response means immediately performs a process corresponding to the input signal, and immediately transmits an output signal as a response signal. Here, the constant detection means that detection is performed at a sampling interval short enough to detect at least an input signal that is normally given. This sampling interval is shorter than at least the output interval of the intermittent output means. Also, “immediately” means that processing is performed quickly enough according to the processing capability of the integrated circuit without spending wasted time such as long waiting time. The IC tag is typically provided with a built-in power source such as a battery or a means for receiving power from the outside through wiring, and the intermittent output means functions based on this.

  In a normal case, this IC tag intermittently transmits radio waves to inform the outside of its existence. For this reason, power consumption can be suppressed and, for example, battery consumption can be avoided. When an input signal is sent from the outside and an action is made, the corresponding output signal is transmitted with a short response time. Therefore, necessary communication can be completed within a limited time during transportation or the like.

  Preferably, in the IC tag of the present invention, the response means outputs an output signal for the corresponding processing and response in preference to the operation of the intermittent output means. That is, when an input signal is received, priority is given to response processing over processing for intermittently outputting an output signal at a set timing. It should be noted that once processing by the response means has been performed, a function is provided such as temporarily stopping the intermittent output means or shortening the sampling interval of the detection means for a while (for example, about 1 minute). The response speed may be switched to a mode for improving the response speed.

  Preferably, in the IC tag of the present invention, the integrated circuit includes setting means for fixing a signal output interval in the intermittent output means to a set value based on an input signal. That is, the output interval in the intermittent output means can be set and changed to a fixed appropriate set value through an input signal for command. Therefore, when a plurality of IC tags are used, such as when an IC tag is attached to each article, a plurality of users can set the output interval of each IC tag to an appropriate common set value or different settings depending on the purpose. What is necessary is just to fix to a value. Note that the fixed set value does not necessarily have to be one time interval. For example, a plurality of set values can be fixed so as to repeat regularly, such as alternately repeating 5 seconds and 7 seconds.

  Preferably, in the IC tag of the present invention, the integrated circuit includes a correspondence table in which a plurality of pieces of identification information and corresponding different set values are registered, and the setting means is provided with identification information based on an input signal. In the case of a failure, the corresponding setting value is set with reference to the correspondence table. This configuration is particularly effective when the identification information is used for other than setting means. For example, by inputting the name of an article with an IC tag as identification information, the article can be specified and the output interval can be changed at the same time.

  Preferably, in the IC tag of the present invention, the identification information is information for identifying a person or an organization related to the use of the IC tag. The person or organization related to the use of the IC tag refers to the owner / owning organization, administrator / management organization, etc. of the IC tag or the article or carrier to which it is attached. For example, when the owner of a pallet as a transport device with an IC tag attached is changed for reuse (reuse), the corresponding output interval can be set by inputting the identification information of the owner. It will be done at the same time.

  Alternatively, in the IC tag of the present invention, the identification information may be information for identifying an article related to use of the IC tag. An article related to the use of an IC tag refers to the name of an article with an IC tag (for example, a product name or model name), or the name of an article that is carried using a carrier with an IC tag.

  The pallet of the present invention is a plastic pallet in which the IC tag is incorporated. Plastic pallets have excellent durability. For this reason, the pallet incorporating the IC tag is reused and used many times. In such a case, the convenience can be improved by incorporating an IC tag having the above-described characteristics.

  The IC tag position calculation device of the present invention is an antenna that receives radio waves intermittently transmitted from the IC tag, and is installed at each of a plurality of different locations, and the radio waves received by each antenna. Calculating means for calculating the installation position of the IC tag based on the comparison of received signals corresponding to. Typically, three or more antennas are installed. When the reach of radio waves is limited or when accuracy is improved by providing redundancy, the number of antennas may be increased as appropriate. The configuration of the IC tag position calculation means can be variously performed. For example, an IC tag position calculation device can be provided by providing a plurality of leads / writers and concentrating signals on any one of the leads / writers. Further, a separate device such as a PC that is provided with a plurality of leads / writers and receives output therefrom may be used as the IC tag position calculation device. Alternatively, it is also effective to provide an IC tag position calculation device by providing only a plurality of antennas and a single reader / writer that performs reception processing. The calculating means calculates the IC tag position by comparing the obtained reception signals. For example, the position can be specified based on the delay amount of the reception time of the same signal.

  Preferably, the IC tag position calculation apparatus of the present invention comprises registration data in which received signal strengths relating to reception of each antenna are registered for a plurality of IC tag positions, and the calculation means refers to the registration data. The installation position of the IC tag is calculated. That is, when the IC tag is placed in various places, data on the received signal strength related to the reception of each antenna is collected and stored in a database. Then, by comparing with this data, the position of the IC tag can be reliably specified.

  The IC tag according to this embodiment will be described below. This IC tag can be used for various well-known applications. Here, as one form that can fully demonstrate its performance, the case where an article is mounted and attached to a pallet used for its transportation and storage is used. The assumed explanation is given.

  FIG. 1 is a schematic configuration block diagram of an IC tag 10 according to the present embodiment. The IC tag 10 includes an IC chip 20, an antenna 60, and a battery 70. These are provided on a base material such as a resin film to form an integrated IC tag 10.

  The IC chip 20 is composed of an integrated circuit created on a resin substrate, and includes a calculation unit 30, a transmission / reception circuit 40, and a storage unit 50 as main functional components. The calculation unit 30 is configured to perform calculation and control according to an incorporated program, and includes a detection unit 32, a response unit 34, a periodic output unit 36, and a setting unit 38. The detection unit 32 constantly monitors the input signal input from the transmission / reception circuit 40 and detects the input of a valid signal. When the detection unit 32 detects a valid input signal, the response unit 34 processes the input signal according to a program. Then, a corresponding output signal is output to the transmission / reception circuit 40 as necessary. The periodic output unit 36 outputs a predetermined output signal to the transmission / reception circuit 40 at set regular intervals. This predetermined output signal is provided for causing an external device to detect the presence of the IC tag 10. The output signal can include identification information of the IC tag 10 registered in the storage unit 50 in advance. The setting unit 38 is provided for setting a regular interval at which the regular output unit 36 transmits an output signal. The setting is performed based on an input signal input from the transmission / reception circuit 40.

  The transmission / reception circuit 40 is a circuit having both a transmission circuit and a reception circuit, and is connected to the arithmetic unit 30 and the antenna 60. A function of transmitting radio waves from the antenna 60 based on an output signal output from the arithmetic unit 30 and a function of processing radio waves acquired by the antenna 60 and converting them into input signals to the arithmetic unit 30 are provided. The frequency of the radio wave to handle is not particularly limited. However, when mounted on a pallet, it is desirable that communication with a relatively long distance is possible, especially in the UHF band (wavelength of about 1 m to 10 cm) or a microwave including the same (wavelength of about 1 m or less). Use becomes effective. The transmission / reception circuit 40 includes a transmission circuit that emits such a frequency as necessary, and performs signal processing.

  The storage unit 50 is configured by a ROM (Read-Only Memory) or a RAM (Random-Access Memory). In the storage unit 50, identification information of the IC tag 10 itself, pallet owner information, and attribute information of an article related to the use of the pallet (article name and its identification number, distribution information such as shipping date and shipping destination) are stored. Information is stored. The storage unit 50 includes a correspondence table 52. The correspondence table 52 is a table including pallet owner candidate information composed of a plurality of pieces of identification information and output interval value candidate information associated with each piece of identification information.

  Pallets are generally used consistently across multiple organizations (factories, warehouses, companies, etc.) in the distribution process. Then, in the final stage, it is reused for transporting and storing other articles. The pallet owner candidate information is identification information (a representative name, an organization name, or an encoded name thereof) of a person who can be an owner in the pallet circulation process including reuse. Further, the output interval value candidate value information is information of the output interval value set to a different value for each pallet owner.

  When identification information about a new owner is input to the reused pallet, the identification information is stored in the storage unit 50. The setting unit 38 refers to the correspondence table 52 and acquires an output interval value corresponding to this identification information. The periodic output unit 36 is set to periodically output an output signal with the output interval value. The output interval value is determined in consideration of the consumption of the battery 70 and the convenience of the external device that receives the output signal. For example, a time of about 5 seconds to 20 seconds is allocated.

  The antenna 60 is configured to transmit and receive radio waves, and is configured by a coil antenna, for example. The battery 70 is provided as a means for supplying power to the IC chip 20. Energy for operating the antenna 60 is also supplied from the battery 70.

  Next, the operation of the IC tag 10 will be described. The IC tag 10 attached to the pallet is input with the pallet owner candidate information and the corresponding output interval value candidate information based on the availability in the circulation process before or after the attachment, and is registered in the correspondence table 52. The Further, identification information of the first pallet owner, attribute information of articles mounted on the pallet, and the like are appropriately input and stored in the storage unit 50. Then, the setting unit 38 acquires an output interval value corresponding to the input identification information of the owner from the correspondence table 52 and sets it in the regular output unit 36.

  The IC tag 10 normally generates a predetermined output signal based on the output interval value set by the periodic output unit 36 and outputs it to the transmission / reception circuit 40. The transmitter / receiver circuit 40 generates a waveform obtained by modulating the carrier wave with this output signal, and transmits the waveform from the antenna 60. For example, when a pallet is stored in a warehouse, a reader / writer installed around the pallet can receive this signal and grasp its presence. It is also possible to add the attribute information of the article to the output signal and send it to the reader / writer.

  When the pallet is transported and passes through the gate where the read / writer is set, it is necessary to perform quick communication between the IC tag 10 and the read / writer. In order to enable this communication, in the IC tag 10, the detection unit 32 is always in a standby state. When an input signal corresponding to the radio wave from the reader / writer is detected, the response unit 34 is configured to immediately perform the corresponding process. For example, when an inquiry about the identification information of the IC tag 10 is made from the input signal, the response unit 34 acquires the identification information from the storage unit 50 and outputs it to the transmission / reception circuit 40 as an output signal. The processing of the response unit 34 is performed immediately when the detection unit 32 detects an input signal. This makes it possible to communicate interactively with an external reader / writer in a short time.

  In the process of reuse, when the pallet is placed under the control of another owner, the identification information of the owner is input to the IC tag 10. And the setting part 38 acquires the output interval value corresponding to this identification information, and changes the output interval of the periodical output part 36. FIG. Therefore, in a warehouse or the like in which the pallet before and after the change are mixed, the reader / writer receives signals generated at different output intervals from the respective pallets. This is effective for preventing interference of a plurality of signals, and is also effective for improving signal detection accuracy and signal filtering based on the difference in output interval. In order to prevent a plurality of signals from synchronizing in a short time period, it is desirable to set the least common multiple of each signal period to be larger than the signal analysis time. For example, if two signals are set to 5 seconds and 10 seconds, they synchronize with a period of 10 seconds (but the phases are not necessarily aligned), but if they are set to 5.5 seconds and 10 seconds, both are 110 seconds. It will synchronize with the period. That is, even if the phases of both are the same, the radio wave transmissions do not overlap each other for 110 seconds (relatively long), and the reception environment is favorable.

  Next, a configuration for detecting the position when the pallet incorporating the IC tag 10 is placed in a warehouse or the like will be described with reference to FIG. An IC tag 10 is incorporated in the vicinity of the center of a pallet 80 made of plastic. A bolted lid is provided on the surface to protect the IC tag 10. Although not shown, generally, an article is mounted on the pallet 80. In addition, the pallet 80 on which articles are mounted may be stacked in a plurality of stages in the vertical direction.

  From the IC tag 10, a radio wave corresponding to the output signal from the periodic output unit 36 is periodically transmitted. This radio wave is received by three lead / writers 90, 92, 94 installed around the pallet 80. The received signal is input to a PC (personal computer) 100 as an IC tag position calculation device.

  The PC 100 includes a calculation unit 102, registration data 104, and a selection communication unit 106 in addition to a general configuration. The calculation unit 102 is formed by the calculation function of the PC 100, and calculates the position of the pallet 80 based on the input signals from the respective reader / writers 90, 92, 94. In the calculation, the registration data 104 created in the storage unit is referred to. The registration data 104 is a database of received signal strengths detected by the respective leads / writers 90, 92, 94 when the pallet 80 is arranged at each storage position in the warehouse. The absolute value and relative magnitude of the signal strength vary depending on each storage position. Therefore, the received signal is compared with the registered data, and the pallet position is calculated by selecting the storage position corresponding to the best matching data. In order to increase accuracy, the registered data may be interpolated and compared in consideration of the possibility of existing between a plurality of registered setting locations.

  The selection communication unit 106 is configured to select a reader / writer used when interactively communicating with the pallet 80. That is, based on the pallet position calculated by the calculation unit 102 or the received signal strength, a reader / writer that can perform the best communication is selected, and only the reader / writer is used for interactive communication. As a result, it is possible to avoid interference that may occur when radio waves are simultaneously transmitted from the plurality of leads / writers 90, 92, 94. A large number of leads / writers can be provided according to the size of the warehouse. Further, the lead / writer may be arranged at different positions in the vertical direction so as to accurately grasp the position of the pallet stacked in the vertical direction.

It is a block diagram which shows schematic structure of the IC tag which concerns on this Embodiment. It is a figure explaining the structure which calculates the pallet position in which the IC tag was incorporated.

Explanation of symbols

  10 IC tag, 20 IC chip, 30 operation unit, 32 detection unit, 34 response unit, 36 periodic output unit, 38 setting unit, 40 transmission / reception circuit, 50 storage unit, 52 correspondence table, 60 antenna, 70 battery, 80 palette, 90, 92, 94 Lead / writer, 100 PC, 102 calculation unit, 104 registration data, 106 selection communication unit.

Claims (9)

An antenna that acquires an input signal by receiving radio waves and transmits a radio wave based on an output signal; an integrated circuit that is connected to the antenna and performs processing based on input of the input signal and processing that outputs the output signal;
In an IC tag with
The integrated circuit comprises:
Intermittent output means for intermittently outputting the output signal at a set timing;
Detection means for constantly detecting the input signal;
When the detection means detects an input signal, a response means that immediately performs corresponding processing and outputs an output signal for response;
An IC tag characterized by comprising: The IC tag according to claim 1,
The IC tag is characterized in that the response means outputs an output signal for the corresponding processing and response in preference to the operation of the intermittent output means. The IC tag according to claim 1,
2. The IC tag according to claim 1, wherein the integrated circuit includes setting means for fixing an output interval of the signal in the intermittent output means to a set value based on an input signal. The IC tag according to claim 3,
The integrated circuit includes a correspondence table in which a plurality of pieces of identification information and the corresponding different setting values are registered,
The setting means, when identification information is given based on an input signal, sets the corresponding setting value with reference to the correspondence table. The IC tag according to claim 4,
The IC tag, wherein the identification information is information for identifying a person or an organization related to use of the IC tag. The IC tag according to claim 4,
The IC tag, wherein the identification information is information for identifying an article related to use of the IC tag.   A plastic pallet in which the IC tag according to any one of claims 1 to 6 is incorporated. An antenna that receives radio waves that are intermittently transmitted from the IC tag according to claim 1, wherein the antenna is installed at each of a plurality of different locations,
Calculating means for calculating the installation position of the IC tag based on comparison of received signals corresponding to radio waves received by each antenna;
An IC tag position calculation device comprising: In the IC tag position calculation device according to claim 8,
With respect to a plurality of IC tag positions, it has registration data in which received signal strengths related to reception of each antenna are registered,
The IC tag position calculating apparatus, wherein the calculating means calculates an installation position of the IC tag with reference to the registration data.

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